package com.yimi.appstore.view;

import java.util.Date;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.view.animation.RotateAnimation;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;

import com.yimi.appstore.R;

/**
 * 下拉刷新listview
 * @author Tank
 *
 */
public class SListView extends ListView  implements OnScrollListener{
	protected static final String TAG = "listview";
	/**松开刷新*/
	protected final static int RELEASE_To_REFRESH = 0;
	/**下拉刷新*/
	protected final static int PULL_To_REFRESH = 1;
	/**正在刷新*/
	protected final static int REFRESHING = 2;
	/**完成*/
	protected final static int DONE = 3;
	/**正在加载*/
	protected final static int LOADING = 4;

	// 实际的padding的距离与界面上偏移距离的比例
	protected final static int RATIO = 3;

	protected LayoutInflater inflater;
	protected Context context;

	protected LinearLayout headView;

	protected TextView tipsTextview;
	protected TextView lastUpdatedTextView;
	protected ImageView arrowImageView;
	protected ProgressBar progressBar;


	protected RotateAnimation animation;
	protected RotateAnimation reverseAnimation;

	// 用于保证startY的值在一个完整的touch事件中只被记录一次
	protected boolean isRecored;

	protected int headContentWidth;
	protected int headContentHeight;

	protected int startY;
	protected int firstItemIndex;

	protected int state;

	protected boolean isBack;

	protected OnRefreshListener refreshListener;

	/**是否可刷新*/
	protected boolean isRefreshable;
	
	/** lvMusic中最后可见项的索引*/
	protected int nLastItem = 0;
	protected OnLoadingListener loadingLister;
	protected boolean isLoadingAble=false;
	protected LinearLayout lLfootView;
	protected int countMax = 20;
	
	protected int downY=0, upY=0;
	/**是否初始化了头部UI、脚部UI*/
	protected boolean haveHead=false, haveFoot=false;
	
	
	
	public SListView(Context context) {
		super(context);
		this.context=context;
	}

	public SListView(Context context, AttributeSet attrs) {
		super(context, attrs);
		this.context=context;
	}
	/**
	 * 初始化视图列表刷新时，头上的UI
	 * @param model
	 */
	public void initHeadView(HeadViewModel model){
		init(model);
		haveHead=true;
	}
	/**
	 * 初始化视图列表加载时，脚下的UI
	 * @param viewId 
	 * @param llId
	 */
	public void initFootView(int viewId, int llId){
		View v=(View)LayoutInflater.from(context).inflate(viewId, null);
		lLfootView=(LinearLayout)v.findViewById(llId);
		addFooterView(v);
		lLfootView.setVisibility(View.GONE);
		setOnScrollListener(this);
		state = DONE;
		isRefreshable = false;
		haveFoot=true;
	}
	protected void init(HeadViewModel model) {
		setCacheColorHint(context.getResources().getColor(android.R.color.transparent));
		inflater = LayoutInflater.from(context);
		headView = (LinearLayout) inflater.inflate(model.getHeadViewId(), null);
		arrowImageView = (ImageView) headView
				.findViewById(model.getArrowId());
		progressBar = (ProgressBar) headView
				.findViewById(model.getProgressBarId());
		tipsTextview = (TextView) headView.findViewById(model.getTipsId());
		lastUpdatedTextView = (TextView) headView
				.findViewById(model.getLastUpdatedId());
		arrowImageView.setMinimumWidth(70);
		arrowImageView.setMinimumHeight(50);
		//在还没有构建headView 之前无法取得View的高与宽
		measureView(headView);
		headContentHeight = headView.getMeasuredHeight();
		headContentWidth = headView.getMeasuredWidth();
		headView.setPadding(0, -1 * headContentHeight, 0, 0);
		headView.invalidate();
		Log.v("size", "width:" + headContentWidth + " height:"
				+ headContentHeight);
		addHeaderView(headView, null, false);
//		setOnScrollListener(this);
		animation = new RotateAnimation(0, -180,
				RotateAnimation.RELATIVE_TO_SELF, 0.5f,
				RotateAnimation.RELATIVE_TO_SELF, 0.5f);
		animation.setInterpolator(new LinearInterpolator());
		animation.setDuration(250);
		animation.setFillAfter(true);
		reverseAnimation = new RotateAnimation(-180, 0,
				RotateAnimation.RELATIVE_TO_SELF, 0.5f,
				RotateAnimation.RELATIVE_TO_SELF, 0.5f);
		reverseAnimation.setInterpolator(new LinearInterpolator());
		reverseAnimation.setDuration(200);
		reverseAnimation.setFillAfter(true);
		state = DONE;
		isRefreshable = false;
	}
	public void onScroll(AbsListView view, int firstVisiableItem, int visibleItemCount,
			int totalItemCount) {
		mOnScroll(view, firstVisiableItem, visibleItemCount, totalItemCount);
	}
	public void onScrollStateChanged(AbsListView view, int scrollState) {
		mOnScrollStateChanged(view, scrollState);
	}
	public void mOnScroll(AbsListView view, int firstVisiableItem, int visibleItemCount,
			int totalItemCount){
		firstItemIndex = firstVisiableItem;
		nLastItem = firstVisiableItem + visibleItemCount;
	}
	public void mOnScrollStateChanged(AbsListView view, int scrollState){
		if(scrollState == OnScrollListener.SCROLL_STATE_IDLE){
			getLoadingData();
		}
	}
	public boolean onTouchEvent(MotionEvent event) {
		switch (event.getAction()) {
		case MotionEvent.ACTION_DOWN:
			if (isRefreshable) {
				if (firstItemIndex == 0 && !isRecored) {
					isRecored = true;
					startY = (int) event.getY();
					Log.v(TAG, "在down时候记录当前位置‘");
				}
			}
			downY=(int) event.getY();
			break;
		case MotionEvent.ACTION_UP:
			upY=(int) event.getY();
			if(upY>downY){
				Log.i(TAG, "isUpScroll=false");
			}else{
				Log.i(TAG, "isUpScroll=true");
				getLoadingData();
			}
			if (isRefreshable) {
				if (state != REFRESHING && state != LOADING) {
					if (state == DONE) {
						// 什么都不做
					}
					if (state == PULL_To_REFRESH) {
						state = DONE;
						changeHeaderViewByState();
						Log.v(TAG, "由下拉刷新状态，到done状态");
					}
					if (state == RELEASE_To_REFRESH) {
						state = REFRESHING;
						changeHeaderViewByState();
						onRefresh();
						Log.v(TAG, "由松开刷新状态，到done状态");
					}
				}
				isRecored = false;
				isBack = false;
			}
			break;
		case MotionEvent.ACTION_MOVE:
			if (isRefreshable) {
				int tempY = (int) event.getY();
				if (!isRecored && firstItemIndex == 0) {
					Log.v(TAG, "在move时候记录下位置");
					isRecored = true;
					startY = tempY;
				}
				if (state != REFRESHING && isRecored && state != LOADING) {
					// 保证在设置padding的过程中，当前的位置一直是在head，否则如果当列表超出屏幕的话，当在上推的时候，列表会同时进行滚动
					// 可以松手去刷新了
					if (state == RELEASE_To_REFRESH) {
						setSelection(0);
						// 往上推了，推到了屏幕足够掩盖head的程度，但是还没有推到全部掩盖的地步
						if (((tempY - startY) / RATIO < headContentHeight)
								&& (tempY - startY) > 0) {
							state = PULL_To_REFRESH;
							changeHeaderViewByState();
							Log.v(TAG, "由松开刷新状态转变到下拉刷新状态");
						}
						// 一下子推到顶了
						else if (tempY - startY <= 0) {
							state = DONE;
							changeHeaderViewByState();
							Log.v(TAG, "由松开刷新状态转变到done状态");
						}
						// 往下拉了，或者还没有上推到屏幕顶部掩盖head的地步
						else {
							// 不用进行特别的操作，只用更新paddingTop的值就行了
						}
					}
					// 还没有到达显示松开刷新的时候,DONE或者是PULL_To_REFRESH状态
					if (state == PULL_To_REFRESH) {
						setSelection(0);
						// 下拉到可以进入RELEASE_TO_REFRESH的状态
						if ((tempY - startY) / RATIO >= headContentHeight) {
							state = RELEASE_To_REFRESH;
							isBack = true;
							changeHeaderViewByState();
							Log.v(TAG, "由done或者下拉刷新状态转变到松开刷新");
						}
						// 上推到顶了
						else if (tempY - startY <= 0) {
							state = DONE;
							changeHeaderViewByState();
							Log.v(TAG, "由DOne或者下拉刷新状态转变到done状态");
						}
					}
					// done状态下
					if (state == DONE) {
						if (tempY - startY > 0) {
							state = PULL_To_REFRESH;
							changeHeaderViewByState();
						}
					}
					// 更新headView的size
					if (state == PULL_To_REFRESH) {
						headView.setPadding(0, -1 * headContentHeight
								+ (tempY - startY) / RATIO, 0, 0);
					}
					// 更新headView的paddingTop
					if (state == RELEASE_To_REFRESH) {
						headView.setPadding(0, (tempY - startY) / RATIO
								- headContentHeight, 0, 0);
					}
				}
			}
			break;
		}
		return super.onTouchEvent(event);
	}

	// 当状态改变时候，调用该方法，以更新界面
	protected void changeHeaderViewByState() {
		switch (state) {
		case RELEASE_To_REFRESH:
			arrowImageView.setVisibility(View.VISIBLE);
			progressBar.setVisibility(View.GONE);
			tipsTextview.setVisibility(View.VISIBLE);
			lastUpdatedTextView.setVisibility(View.VISIBLE);
			arrowImageView.clearAnimation();
			arrowImageView.startAnimation(animation);
			tipsTextview.setText("松开刷新");
			Log.v(TAG, "当前状态，松开刷新");
			break;
		case PULL_To_REFRESH:
			progressBar.setVisibility(View.GONE);
			tipsTextview.setVisibility(View.VISIBLE);
			lastUpdatedTextView.setVisibility(View.VISIBLE);
			arrowImageView.clearAnimation();
			arrowImageView.setVisibility(View.VISIBLE);
			// 是由RELEASE_To_REFRESH状态转变来的
			if (isBack) {
				isBack = false;
				arrowImageView.clearAnimation();
				arrowImageView.startAnimation(reverseAnimation);
				tipsTextview.setText("下拉刷新");
			} else {
				tipsTextview.setText("下拉刷新");
			}
			Log.v(TAG, "当前状态，下拉刷新");
			break;
		case REFRESHING:
			headView.setPadding(0, 0, 0, 0);
			progressBar.setVisibility(View.VISIBLE);
			arrowImageView.clearAnimation();
			arrowImageView.setVisibility(View.GONE);
			tipsTextview.setText("正在刷新...");
			lastUpdatedTextView.setVisibility(View.VISIBLE);
			Log.v(TAG, "当前状态,正在刷新...");
			break;
		case DONE:
			headView.setPadding(0, -1 * headContentHeight, 0, 0);
			progressBar.setVisibility(View.GONE);
			arrowImageView.clearAnimation();
			arrowImageView.setImageResource(R.drawable.arrow);
			tipsTextview.setText("下拉刷新");
			lastUpdatedTextView.setVisibility(View.VISIBLE);
			Log.v(TAG, "当前状态，done");
			break;
		}
	}
	/**
	 * 设置向下拉，刷新数据响应事件
	 * @param refreshListener
	 */
	public void setOnRefreshListener(OnRefreshListener refreshListener) {
		this.refreshListener = refreshListener;
		isRefreshable = true;
	}
	/**
	 * 设置滑动到最下面，加载数据响应事件
	 * @param loadingListener
	 */
	public void setOnLoadingListener(OnLoadingListener loadingListener){
		this.loadingLister=loadingListener;
		isLoadingAble=true;
	}

	public interface OnRefreshListener {
		public void onRefresh();
	}
	public interface  OnLoadingListener {
		public void onLoading();
	}

	public void onRefreshComplete() {
		state = DONE;
		lastUpdatedTextView.setText("最近更新:" + new Date().toLocaleString());
		changeHeaderViewByState();
	}
	/**
	 * 刷新数据 
	 */
	protected void onRefresh() {
		if (refreshListener != null) {
			refreshListener.onRefresh();
		}
	}
	/**
	 * 加载数据
	 */
	protected void onLoading(){
		if(loadingLister!=null){
			loadingLister.onLoading();
		}
	}

	// 此方法直接照搬自网络上的一个下拉刷新的demo，此处是“估计”headView的width以及height
	protected void measureView(View child) {
		ViewGroup.LayoutParams p = child.getLayoutParams();
		if (p == null) {
			p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,
					ViewGroup.LayoutParams.WRAP_CONTENT);
		}
		int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0, p.width);
		int lpHeight = p.height;
		int childHeightSpec;
		if (lpHeight > 0) {
			childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight,
					MeasureSpec.EXACTLY);
		} else {
			childHeightSpec = MeasureSpec.makeMeasureSpec(0,
					MeasureSpec.UNSPECIFIED);
		}
		child.measure(childWidthSpec, childHeightSpec);
	}
	private void showLoadingProgress(){
		if(lLfootView!=null){
			lLfootView.setVisibility(View.VISIBLE);
			setSelection(getAdapter().getCount()-1);
		}
	}
	public void onLoadingComplete(){
		if(lLfootView!=null){
			lLfootView.setVisibility(View.GONE);
		}
	}
	public void setAdapter(BaseAdapter adapter) {
		if(lastUpdatedTextView!=null){
			lastUpdatedTextView.setText("最近更新:" + new Date().toLocaleString());
		}
		super.setAdapter(adapter);
	}
	/**
	 * 当ListView中总项数超过设置的最大值，滑动到最下面才会加载数据
	 * @param num
	 */
	public void setCountMax(int num){
		countMax=num;
	}
	/**
	 * 加载数据
	 */
	protected void getLoadingData(){
		int n=0;
		if(haveHead){
			n++;
		}
		if(haveFoot){
			n++;
		}
		if (getAdapter()!=null&&nLastItem == getAdapter().getCount() && getAdapter().getCount()-n>=countMax){
			if(isLoadingAble==true){
				if(lLfootView!=null && lLfootView.getVisibility()==View.GONE){
					Log.i(TAG, "加载……");
					showLoadingProgress();
					onLoading();
				}
			}
		}
	}

}
